Thomas c



UNTTED STATES.

THOMAS C. ROCHE, OF BROOKLYN, ASSIGNOR TO E. & H. T. ANTHONY & CO

PATENT ()FFICE.

OF NEV YORK, N. Y.

COMPOSITION FOR HOLDING PHOTOGRAPHIC PAPER ON lTS SUPPORT, &c.

SPECIFICATION forming part of Letters Patent No. 346,224, dated July 27,1886.

Application filed October 28. 1885. Serial No. 18l,155. No specimens.)

To all whom, it may concern.-

Be it known that I, THOMAS C. ROCHE, of Brooklyn, in the county ofKings, in the State of New York, have invented an Improved Compositionfor Holding Sensitive Photographic Paper on its Support During theExposure of the Paper in the Camera, of which the following is aspecification.

My composition consists of the following ingredients, combined in theproportions stated: rubber, three ounces; pitch, one-half ounce; solventfor the same, one pint. The solvent may consist of benzole, turpentine,bisulphide of carbon, or any of the solvents of pitch and rubber; but Iprefer to use benzole. I dissolve the rubber in the benzole or othersolvent, and when a thorough solution is effected I thin it to thedesired consistency with the solvent, which in the present case isbenzole.

I then add the pitch and allow it to stand,with occasionalagitation,until a complete solution of the pitch is effected. Thiscompound I designate as compound No. l. I then prepare compound No. 2,which consists of the following ingredients, in the proportions stated:rubber, three ounces; benzole, sixteen ounces; yellow beeswax, twodrains. I dissolve the rubber in the benzole, and after thinning it tothe desired consistency with the benzole I add 0 the yellow beeswax andallow it to dissolve.

I then mix compound No. 1 and compound No. 2 together, employing eitherequal parts of each or mixing them in any other desired proportion.

In lieu of the common glass plate ordinarily used within the camera forcarrying or supporting the sensitive film, I employ a support consistingof a thin plate or sheet composed of wood, metal, paper,card-board, orother suita- 0 ble material, the surfaces or faces of which are smooth,and if the material is of a porous, absorbent nature I fill the surfacesthereof with a suitable filling or varnish. Upon the face or faces ofthis support, when dry, I spread a thin 5 coating of the compositionabove described by means of a brush, or in any other convenient manner,and allow it to dry until the volatile matters have escaped. The pitchand the bees Wax added to the rubber render the mixture permanentlytacky, so that it will possess suf- 5o ficient adhesiveness to attachitself to the surface of the sensitive paper, but will not penetrate thesensitive paper or be absorbed thereby, nor will it in any manner injureor permanently affect the paper. The sheet of sensitized paper isapplied by its back to the face of the above-described support, and theface of the paper is then gently rubbed, so as to cause the tackycoating of the support to grasp, hold, and smoothly support every partof the sensitive paper, rendering it impossible for any portion of thepaper to curl, wrinkle, or get out of shape. The support, with itsattached pa per and tacky material interposed between the face of thesupport and the sensitive paper, is now placed in a plate-holder in theordinary manner and introduced Within the photographic camera, and thesensitive paper is exposed to the light fortaking the picture in theusual way, after which the plate-holder and support are removed from thecamera for the development of the picture by the usual method, the paperbeing removed from its support by lifting one corner of the paper andstripping it off from the support. The composition applied to thesupport is of a nature that will admit of removing the paper from thesupport without removing the composition along with it. It will alsoretain its tacky quality, so that one coating of the tacky compositionmay be used repeatedly and will last a long time. WVhenever any portionof the tacky facing be comes worn away or exhausted,it may be readilyrenewed by the application thereto of a fresh portion of the tackycomposition.

It is obvious that either compound N o. 1 or compound No. 2 will beefficient in retaining the sensitive paper on its support, so that I donot limit or confine myself to a mixture of these two compounds. It isalso obvious that I may substitute for the pitch or wax a fixed oil orany substance that will render the support permanently tacky.

By the employment of the above composition the sensitive photographicpaper is held upon its support with sufficient firmness to permit of themanipulation of the paper in the plate-holder and camera; but thequality of the tacky surface secured in my composition is such as topermit of the ready removal of the sensitive paper from the tackysurface without removing any appreciable quantity of the compositionfrom the photographic-paper support.

I do not claim, broadly, as my invention the construction of acamera-support having its face or faces provided with a tacky substancefor grasping and holding the sensitive photographic paper upon saidsupport, as hereinbefore described, as said device is the inven tion ofEdward Anthony, of New York, who has applied or is about to apply for apatent thereon.

My invention herein described is intended to relate to and include onlymy said compo sition of matter.

What I claim, and desire to secure by Letters Patent of the UnitedStates, is

1. The herein described composition for the camera, the same consistingof rubber,"

pure beeswax, pitch, and a solvent, in about the proportions stated.-

holding sensitive photographic paper on its THOMAS C. ROCHE.

Witnesses: O. SEDGWIOK,

A. E. BEACH.

